The within described invention relates to the field of radar, millimeter wave devices, and to Gunn oscillators in particular.
In devising a mixing device for signals in the millimeter wave frequency range (30 to 300 GHZ) special problems may arise. A usual manner of providing a mixing function in such enviroments is to use hybrid couplers, having Schottky Barrier diodes, to create a balanced mixer. However, some of the disadvantages of such systems include excessive noise, high as 12.5 db DSB for example, and that the units can burn out at reaching a relatively low power level, 100 milliwatts CW, RF power for example. Yet there is a demand for ever higher power levels in modern communications equipment and a necessity for even greater fidelity in communication for which noise is detrimental. Improvement of devices for conventional mixing, especially in these two respects would therefore be greatly desirable.
The application relates to an improved mixer which is considered to be patentably distinct from our earlier invention described and claimed in our copending patent application Ser. No. 507,886, filed June 27, 1983, and which relates to a dual Gunn diode self-oscillating mixer.